1. Field of the Invention
The present invention relates to a computer peripheral. More specifically, the present invention relates to a computer peripheral that is connected to a computer (host computer) when using it, and can reduce power consumption at a standby mode of the computer peripheral.
2. Description of the Prior Art
Various devices such as a floppy disk drive (FDD), an optical disc drive are used as a computer peripheral. Some of the various devices may be embedded in a host computer and used as an internal device, and other of the various devices may be externally installed outside a computer and used as an external device.
Some computer peripherals have no power source therein and can operate by receiving a power supply from a computer (host computer). For example, most computer peripherals connected to a host computer via a universal serial bus (USB) cable generally operate by receiving the power supply from the host computer.
In such a conventional computer peripheral, a constant current flows at both an operation mode and a standby mode of the computer peripheral. For example, in case of a FDD that receives a power supply from a host computer via a USB connection, a current constantly flows into a motor driver IC for a spindle motor, thereby consuming electric power at a standby mode in vain.
As described above, there was a problem that a current equal to the current flowing at the operation mode constantly flows even at the standby mode in such a conventional computer peripheral, thereby using the ability to supply electric power of a host computer in vain.
Further, there was a problem that in the case where the total amount of current which computer peripherals require exceeds standards of power consumption for the USB or the like, this excess gives rise to an overload to a power supply unit of the host computer or an incorrect operation of the computer peripheral.